Individual serovars can be further characterised (typed) by a number of methods, including phage typing and antibiotic resistance profiles. The most severe form of Salmonella infection is typhoid fever caused by serovars adapted to a human host, such as S. Typhi and S. Paratyphi. But infection by non-typhoid salmonellae is much more common and usually causes gastroenteritis, with symptoms including diarrhoea, abdominal pain, nausea and vomiting lasting from 1-7 days. Healthy adults rarely suffer other symptoms and the mortality rate is